Bulk-Voltage Driver Circuit for Standby Leakage Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
As integration of integrated circuits (ICs) increases, so does the number of output drivers, leading to increased leakage current and power consumption, which affects the operation characteristics and competitiveness of mobile devices, especially in low-power systems where high power-consumption semiconductor memory devices are not viable.
Innovation Solution
A driving device that controls the power source of a pre-driver during standby mode to reduce channel-off leakage current by using a bulk-voltage controller and control signal generator to manage voltage levels across pre-drivers and output drivers, preventing unnecessary transistor activation during standby.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the number of output drivers is increased to improve integration degree, then productivity is improved, but leakage current increases leading to higher power consumption
Solution Approach 1:
The driver circuit is segmented into multiple independent output drivers, each with separate control mechanisms. This allows individual management of each driver's power state, enabling the system to maintain high integration while controlling overall leakage current through selective activation of only necessary drivers.
Solution Approach 2:
The patent changes the voltage parameter by introducing a bulk voltage control mechanism that adjusts the substrate potential of transistors. By dynamically changing the bulk voltage parameter, the patent reduces off-state leakage current in transistors while maintaining normal operation when drivers are active, thus reducing total power consumption in high-integration systems.
2Speed
If transistor channel length is reduced to improve switching speed, then speed is improved, but off-leakage current increases in standby mode
Solution Approach 1:
The patent applies bulk voltage modulation to change the electrical parameters of transistors with short channel lengths. By adjusting the bulk-to-source voltage difference, the patent controls the threshold voltage and reduces off-leakage current without compromising the short channel's high-speed switching capability during active operation.
Solution Approach 2:
The patent introduces dynamic bulk voltage control that adapts to the operational state of transistors. During standby mode, the bulk voltage is adjusted to minimize leakage, while during active switching, the bulk voltage returns to normal levels to maintain high-speed performance. This dynamic adjustment resolves the contradiction between speed and leakage.
3Loss of energy
If bulk voltage is increased to reduce off-leakage current, then loss of energy is reduced, but device complexity increases due to additional control circuits
Solution Approach 1:
The bulk voltage controller is designed to serve multiple output drivers simultaneously with a single control mechanism. This multi-functional approach reduces the overall complexity compared to having separate control circuits for each driver, while still achieving effective leakage current reduction across the entire integrated circuit.
Solution Approach 2:
The patent merges the bulk voltage control functionality into an integrated controller that manages multiple transistors and drivers. By combining control functions and sharing resources, the patent reduces the total number of discrete control circuits needed, thereby limiting the increase in device complexity while maintaining effective leakage control.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively reduces leakage currents (IDD2, IDD6, DPD) and Deep Power Down currents, enhancing the operational efficiency and competitiveness of low-power mobile devices by minimizing power consumption and preventing DC failures.
Implementation Method 1
a bulk-voltage controller configured to selectively control bulk-voltage levels of the pre-driver and the output driver in response to the control signal
Implementation Method 2
change a voltage level of the drive control signal in response to a control signal so as to selectively provide the changed voltage level
Data Source
AI summary
A driving device is disclosed, which relates to a technology for reducing consumption of a leakage current unnecessary for a driver circuit. The driving device includes: a pre-driver configured to output a drive control signal upon receiving a power-supply voltage in response to an input signal, and change a voltage level of the drive control signal in response to a control signal so as to selectively provide the changed voltage level; an output driver configured to receive the power-supply voltage in response to the drive control signal, and output the received power-supply voltage to an output terminal; and a bulk-voltage controller configured to selectively control bulk-voltage levels of the pre-driver and the output driver in response to the control signal.